Small Engines (Lawn Mowers, etc.): CRAFTSMAN /HONDA, axle assembly, pulley

Question
I have a self propelled push mower everything works fine except it no longer self propells. What should i look for?

Answer
There are a number of things to look for. First, check if the handle or lever that activates the self-propelling mechanism is still springy when you pull/push it. When you do, it should spring back when the start lever is released, or when you let go. If it's a belt drive, flip the mower over, and look right above the blade. You should see a pulley. If there's no belt on it, then you need a new belt. If there is, then flip the mower back over, and remove the wheels that propel the mower. Check the gearing. If the gears move freely, then you need a new axle assembly.